Discharge apparatuses for media, which are in particular suitable for spraying a fluid preferably containing at least one pharmaceutical substance are generally known. Such a discharge apparatus on which the preamble is based can e.g. be gathered from DE 197 53 147 A1.
Such a discharge apparatus has a casing, an actuator being movable relative to said casing. With each actuator stroke a discharge process takes place and during each discharge process a specific fluid quantity is discharged from the container located in the casing.
Particularly when using such discharge apparatuses in conjunction with pharmaceutical substances, it is important that the same medium quantity is discharged during each actuating stroke. Since during the actuations of the actuator an ever greater air quantity collects in the medium container it is no longer necessarily ensured with decreasing medium supply that in each dispenser actuating position only medium is discharged in the discharge apparatus. There can also be secondary air suction, so that a smaller medium quantity and therefore a smaller substance quantity is discharged. This is particularly disadvantageous if it is necessary to ensure a very precise dosage of the active substance not only during a single actuation, but also over several actuations. This problem more particularly arises if it is necessary to wait a certain minimum period between two successive applications of the medium.
It can also be advantageous in other cases for the orientation of the discharge apparatus with respect to the environment to be fixed, so that a correct application or administration is ensured.
The problem of the invention is to further develop the discharge apparatus according to the preamble in such a way that it is possible to ensure the discharge of a predetermined medium volume during each individual actuating stroke.
A discharge apparatus according to the invention for media has a casing on which is located an actuator. During each actuation of the actuator an actuating stroke takes place and consequently a specific volume of the medium stored in the casing is discharged. According to the invention gravity dependently operating arresting or blocking means are constructed in such a way that as a function of the spatial position of the discharge apparatus they can block or arrest the performance of an actuating stroke.
According to a preferred development of the invention the gravity dependently operating arresting means are movably mounted, mechanically acting operating or switching means, which are preferably so guided that under a predetermined spatial orientation of the discharge apparatus, said operating means block an actuating stroke of the actuator. The operating means are preferably balls guided in a cam or curved path and whose diameter is advantageously smaller than the path of an actuating stroke of the actuator and preferably the diameter of a ball almost corresponds to the path of an actuating stroke.
According to a preferred development of the invention the curved path at least approximately is in the form of an inclined plane. Preference is also given to a construction in which the curved path has at least one dwell trough defining a holding position and intended to receive the balls. It is also preferable for the dwell trough to be positioned in the vicinity of the curved path in which the balls block an actuating stroke of the actuator.
According to an advantageous development of the invention at least two operating means movable in different, independent directions are provided. The operating means are preferably constructed in such a way that they in each case have on one side a stop member and on the side of the operating means remote from the stop member is constructed the position blocking the actuating stroke of the actuator and where in each case a pair of operating members is provided, whose stop member is constructed on opposite sides of the movement path. Preferably the operating means of a pair are oriented in a common direction and formed on opposite sides of the discharge apparatus.
Preference is also given to a construction in which the blocking means block an actuating stroke, if the divergence of the discharge direction of the discharge apparatus from the vertical exceeds an angle of at least 30.